Easily import both reference and user-specified datasets for navigation system design and testing projects.
Organic Navigation Reference Data
onavdata module provides easy access to both reference datasets and user-specified datasets for the design, development, and testing of navigation algorithms. Additionally, useful utilities are included for working with common navigation sensors.
Reference datasets are well understood, documented, and purged of data logging artifacts. A valuable set of reference datasets are included with
onavdata. They are well-understood yet realistic datasets, making them useful for testing a data processing script or candidate algorithm.
User-specified datasets are managed and made available via the same
onavdata interface as the reference datasets, with the exception that these datasets are added by the user. Thus, the transition from reference to experimental datasets is relatively smooth.
Utilities are included for facilitating common unit conversions or getting data columns for common navigation sensors.
The primary data structure used by
onavdata is the Pandas DataFrame. A basic familiarity with DataFrames is recommended (e.g. one-liners to down-sample, average, plot, or save to CSV). All configuration or meta data files use the easily understood TOML format.
List Data Available
All data sets are referenced using their shortname.
>> import onavdata >> onavdata.print_shortnames() 2011 UMN-UAV GPSFASER1 2012 UMN-UAV FASER5 2012 UMN-UAV GPSFASER3 2012 UMN-UAV THOR60 2012 UMN-UAV THOR75 2012 UMN-UAV THOR77 2012 UMN-UAV THOR79 2021-04-27 HGuide n380 Car Drive Between Traffic Lights 2021-04-27 HGuide n380 Car Hill Driving SIM-MEASURED-CAR NORTH FIXED-SPEED FIXED-HEADING SIM-MEASURED-CAR NORTH FIXED-SPEED VARY-HEADING SIM-MEASURED-CAR NORTH VARY-SPEED FIXED-HEADING SIM-MEASURED-CAR NORTH VARY-SPEED VARY-HEADING SIM-PERFECT-CAR NORTH FIXED-SPEED FIXED-HEADING SIM-PERFECT-CAR NORTH FIXED-SPEED VARY-HEADING SIM-PERFECT-CAR NORTH VARY-SPEED FIXED-HEADING SIM-PERFECT-CAR NORTH VARY-SPEED VARY-HEADING
Load a Reference Data Set
An arbitrary data set can be loaded if no shortname is specified. In this case the data from
2014 UMN-UAV THOR77 was returned.
>> import onavdata >> df = onavdata.get_data() get_data(): No shortname specified so choice will be arbitrary. Returning: 2014 UMN-UAV THOR77 >> df.head() AccelX (m/s^2) AccelY (m/s^2) AccelZ (m/s^2) ... AngleHeading (rad) AnglePitch (rad) AngleRoll (rad) TimeFromStart (s) ... 0.00 1.862795 -0.392167 -9.673463 ... 1.004700 0.192806 0.006130 0.02 1.895476 -0.424848 -9.640783 ... 1.004225 0.192856 0.006130 0.04 1.895476 -0.359487 -9.706145 ... 1.003786 0.192888 0.006259 0.06 1.895476 -0.392167 -9.640783 ... 1.003258 0.192990 0.006354 0.08 1.895476 -0.392167 -9.640783 ... 1.002907 0.193056 0.006482 [5 rows x 12 columns]
Load User-Specified Datasets
examples/simple_data_load.py file shows an example of adding a user-specified dataset using the
add_dataset() method. There are two main requirements:
- Path to a file named
shortnames.txt, populated with a suitable entries for each dataset. Namely:
- A shortname for the dataset
- Path to dataset file(s)
- Path to an associated meta data file for the dataset (more on this below)
onavdataof the user-specified datasets by using the
shortnames.txt can be used (e.g. using one per project). Assuming no conflicting shortnames, there is no issue with adding multiple user-specified datasets.
Dataset Meta Data
Each dataset must have an associated meta (data) file. The meta file contains parameters necessary to pre-process and load the dataset in a clean state. Steps like adding a time-index, renaming columns, rotating axes, dropping rows where data is unreliable... all of these and more are made possibly by parameter specifications in the meta file. Hence, the data loading process handles the steps to clean a raw dataset. The goal is for experimental user-specified datasets to have similar quality (e.g. remove unreliable transients) and attributes (e.g. columns names) as reference datasets.
Note that more than one dataset can point to the same meta file. This is commonly done when multiple datasets are collected using the same device or setup.
Sample Meta Data File Format
Below is an example meta file with all possible parameters demonstrated. Comment lines begin with the
# symbol. In practice, only the parameters needed should be included.
# Define Sampling Time. # Checks for a `TimeFromStart (s)` column (after column renaming) or uses the # specified sampling freq. The latter is only used if the former doesn't exist. # 'SampleFreq (Hz)' = 200 # Rows to skip before loading dataset (e.g. multi-line header). 'skip-lines'= 0 # Option to drop unnamed columns. 'drop-unnamed' = True # Specify list of columns to load (or list of columns to drop `columns-drop`). 'columns-use' = ['Time (s)', 'Ax', 'Ay', 'Az', 'GNSSNumSV', 'GNSSFix'] # 'columns-drop' = ['Empty Channel 1'] # Drop rows if column has a matching entry with a list of values. [drop-rows-where] 'GNSSNumSV' =  # Only keep rows if column has a matching entry with a list of values. [keep-rows-where] 'GNSSFix' =  # Only keep rows where column has entries GREATER than, LESS than, or BETWEEN. [keep-rows-gt] 'Time (s)' = 5 [keep-rows-lt] 'Time (s)' = 65 [keep-rows-between] 'Az' = [-1, 1] # Override default dtypes # The dtype names must be acceptable to pd.DataFrame.astype() function. [columns-dtype] 'GNSSNumSV' = 'int32' # Round columns to decimals specified. [columns-round-decimals] 'Ax' = 3 'Ay' = 3 'Az' = 3 # Scale data for specific columns (e.g. change units). [columns-scale] 'Ax' = 9.81 'Ay' = 9.81 'Az' = 9.81 # Rename columns: 'old name' = 'new name' [columns-rename] 'Time (s)' = 'TimeFromStart (s)' 'Ax' = 'AccelX (m/s^2)' 'Ay' = 'AccelY (m/s^2)' 'Az' = 'AccelZ (m/s^2)' # Apply rotations to groups of columns which start with key. # Notes: # Columns found are sorted so as to get order: X->Y->Z # Key entries should refer to the renamed column names [Rsensor2body] 'Accel' = [[ 0, -1, 0], [-1, 0, 0], [ 0, 0, -1]] # The columns with the `Accel` prefix will be found and the defined rotation # matrix applied. # Add additional columns with constant values, or by copying another column. [add-columns] 'AnglePitch (rad)' = 0.0 'Temperature (C)' = 28.0 'No. of Satellites' = 'GNSSNumSV'
Download the file for your platform. If you're not sure which to choose, learn more about installing packages.